Surfactants are amphiphilic compounds comprising a polar or ionic head group and a hydrophobic tail. Anionic surfactants have important commercial applications as wetting agents, detergents, oil additives and enhanced oil recovery agents. Anionic sulfonate surfactants are a commercially important class of detergents. Surfactants used in enhanced oil recovery processes also typically have sulfonate or sulfate polar head groups due to the aqueous solubility of such compounds in the presence of hard cations often present in such environments, such as Mg.sup.2+ and Ca.sup.2+. Such surfactants include alkylsulfonates, alkylarylsulfonates and petroleum sulfonates. More recently, the development of surfactant-based enhanced oil recovery methods has slowed dramatically, due, in part, to high surfactant costs. As a result, the development of low-cost surfactants derived from waste products, such as lignin, has been an active area of research in the petroleum industry.
Aromatic sulfonates, such as toluene sulfonate and cumene sulfonate, find application as hydrotropes, substances that increase the aqueous solubility of a material which otherwise has only limited aqueous solubility. Current research in the area of hydrotropes is focused on the development of materials having multifunctional properties.
Environmental concerns in regard to biodegradability and toxicity, as well as a desire for multifunctional compositions has driven research directed toward the development of new surfactants for detergents and other applications. There is, thus, a need for new, inexpensive starting materials for the preparation of surfactants, particularly surfactants which are suitable for use in an enhanced oil recovery process.